@article { ISI:000259337100008,
	title = {Heteronuclear dipolar decoupling effects on multiple-quantum and satellite-transition magic-angle spinning NMR spectra},
	journal = {Magnetic Resonance in Chemistry},
	volume = {46},
	number = {10},
	year = {2008},
	month = {OCT},
	pages = {948-954},
	publisher = {JOHN WILEY \& SONS LTD},
	type = {Article},
	address = {THE ATRIUM, SOUTHERN GATE, CHICHESTER PO19 8SQ, W SUSSEX, ENGLAND},
	abstract = {<p>We here report on the influence of heteronuclear dipolar decoupling on the Al-27 3QMAS, 5QMAS, and the double-quantum filter-satellite-transition magic-angle spinning (DQF-STMAS) spectra of a strongly dipolar-coupled system, gibbsite. The requirements for heteronuclear dipolar decoupling increase with the order of coherence evolving in the indirect dimension of a two-dimensional (2D) experiment. The isotropic line width of the high-resolution 2D spectra, in samples like gibbsite, is composed of four parts: the distribution of isotropic shifts (delta(ISO), delta(QIS)), the homogeneous broadening related to the proton-proton flip-flop terms, the Al-27-Al-27 homonulcear dipolar couplings, and the H-1-Al-27 heteronuclear dipolar couplings. It is shown that, even in the case of gibbsite, where a strong proton-proton bath exists, the main resolution limiting factor in these experiments resides in the H-1-Al-27 dipolar interaction. Copyright (C) 2008 John Wiley \&amp; Sons, Ltd.</p>},
	keywords = {heteronuclear broadening, heteronuclear decoupling, homogeneous broadening, MQMAS, quadrupolar nuclei, Solid-state NMR, STMAS, TPPM},
	issn = {0749-1581},
	doi = {10.1002/mrc.2286},
	author = {Ganapathy, Subramanian and Delevoye, L. and Arnoureux, J. P. and Madhu, Perunthiruthy K.}
}
@article { ISI:000274459600009,
	title = {Evidence for the co-existence of distorted tetrahedral and trigonal bipyramidal aluminium sites in SrAl12O19 from Al-27 NMR studies},
	journal = {Solid State Communications},
	volume = {150},
	number = {5-6},
	year = {2010},
	month = {JAN},
	pages = {262-266},
	publisher = {PERGAMON-ELSEVIER SCIENCE LTD},
	address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND},
	abstract = {<p>Strontium aluminate, SrAl12O19, is a ceramic material having the hexagonal magnetoplumbite-type structure, with multiple Al coordination environments. An earlier low-field Al-27 solid-state NMR study reported five different Al sites in this system: one AlO4, one AlO5, and three AlO6 sites; whereas a later high-field study showed that the AlO5 site is a distorted AlO4 site with a very large quadrupolar coupling constant (similar to 20 MHz). Our magic angle spinning (MAS) and 3-quantum magic angle spinning (3QMAS) NMR studies at 7.05 T unambiguously show evidence for an AlO5 site. However, evidence for the presence of a distorted AlO4 site is obtained from studies at high fields (16.4 and 17.6 T), in addition to the AlO5 site. Thus the present solid-state NMR studies give evidence for the simultaneous presence of both the five-coordinated and distorted four-coordinated sites in this system. (C) 2009 Elsevier Ltd. All rights reserved.</p>},
	keywords = {Local structure, MQMAS, Nuclear magnetic resonance, Strontium aluminate},
	issn = {0038-1098},
	doi = {10.1016/j.ssc.2009.11.008},
	author = {Harindranath, K. and Viswanath, K. Anusree and Chandran, C. Vinod and Braeuniger, Thomas and Madhu, Perunthiruthy K. and Ajithkumar, Thalasseril G. and Joy, Pattayil Alias}
}
